There is an ongoing need for highly integrated radio systems in low-cost silicon platforms to address field-deployable and massively-producible applications in military systems and commercial markets, including wireless sensor networks, medical implantable devices, and swarm multi-robot systems. However, these applications typically place stringent requirements on the radio solutions which need to offer an ultra-compact form-factor, an ultra-low power consumption, a sufficient communication distance, and a useful data rate. Most existing integrated radio solutions, however, cannot satisfy such demanding SWaP (Size-Weight-and-Power) requirements. Accordingly, it remains a challenge to push the power consumption limit in conventional radio architectures even with various low-power design techniques. Moreover, the physical size of GHz or mm-Wave radios is fundamentally dominated by the size of the antenna at millimeter or even centimeter scales.
The continuous device scaling in silicon IC technologies (e.g., CMOS, SiGe HBT) has opened the door to radios operating at mm-Wave and THz frequencies. Such a high operating frequency allows a drastic reduction of the antenna sizes as well as the whole radio form-factor to the sub-millimeter scales. However, most nm-Wave and THz radios consume substantial DC power, often from hundreds of milli-watts to watts, incompatible with field-deployable applications.